valve springs

You mentioned in the op that it was a race only motor that being the case I wouldn't worry about changing the spring. Here's my line of thought for one ,miles will be very limited so spring pressure gets a little more forgiving in comparison to a street motor that's racking up miles that can work against a heavy spring load(lobe ware) Also in a race application a little more spring is always better than not enough in my opinion there's always a chance of an RPM Spike and it's good to have a stout spring. But if you are determined to lighten the spring load a little I would look into retainers as mentioned previously different styles can reduce spring load.